E-Mail reply construct, ''in-reply-to' header" not used by Trengo
We have a remark from a customer that Trengo does not use the ''in-reply-to' header when replying to e-mail messages. This is not truly a compliant method of replying to an mail because it doesn't keep track of the original and succeeding message id's. In some cases this will lead to wrong conversation grouping when automatically grouping messages only on subject and sender. If the receipent is not autogrouping it will break-up the conversation. This causes ongoing problems with FrontApp for instance.